DESCRIPTION: The proposal intends to extend and refine the investigators' previous observations on T cell turnover in HIV infection using a stable isotope-mass spectrometric (MS) method in which cellular DNA is labelled with 2-H glucose. Studies will be performed in seronegative controls and in seropositive subjects before and after antiretroviral therapy. The goals of the project are: 1) to attempt to simplify the method with shorter time of administration and/or oral administration, 2) utilize a different MS analytical process to reduce cost and 3) use the method to follow additional subpopulations of cells, including antigen specific and V-beta subpopulations.